Arai in Fall
In fall (September, October and November), Arai sees average daytime highs around 18°C and overnight lows near 11°C, with 558 mm of precipitation over about 52 wet days across the season. It is the 2nd-warmest season and the 3rd-wettest season.
Over the season highs ease from about 26°C in early September to 9°C by late November. The sky is clear or mostly clear about 18% of the time across fall, and the air most often feels dry.
Fall is Arai's 2nd-best season to visit on our travel score. For the whole year in context, see Arai's year-round climate.
- Avg daytime high
- 18°C
- 2nd-warmest season
- Avg overnight low
- 11°C
- Precipitation
- 558 mm
- 52 wet days
- Avg wind
- 7 km/h
- Travel score
- 4.3
- 2nd-best season
- Months
- Sep · Oct · Nov
Temperature in Arai in Fall
Over the season highs ease from about 26°C in early September to 9°C by late November.
A typical fall day in Arai reaches about 18°C and drops to 11°C overnight. The warmest of the three months is September, the coolest November.
How fall really feels in Arai
Once humidity and wind are folded in, fall brings about 0 days that feel above 32°C and 4 that feel at or below 0°C.
The story in fall is cold — wind chill drags the overnight "feels like" below the raw low.
Arai weather by month
How the three fall months (September, October and November) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Snow days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|---|
| Jan | 3° / -3° | 242 | 25.4 | 23.5 | 9.7 | 0.0 |
| Feb | 3° / -3° | 179 | 20.9 | 18.4 | 10.6 | 0.0 |
| Mar | 7° / -1° | 162 | 20 | 13.3 | 11.7 | 0.6 |
| Apr | 13° / 4° | 117 | 14.8 | 2.7 | 12.9 | 3.4 |
| May | 19° / 10° | 130 | 14 | 0 | 14 | 5.6 |
| Jun | 23° / 16° | 166 | 16.5 | 0 | 14.5 | 5.4 |
| Jul | 26° / 20° | 249 | 21.1 | 0 | 14.3 | 4.8 |
| Aug | 28° / 21° | 191 | 19.7 | 0 | 13.4 | 4.8 |
| Sep | 24° / 17° | 204 | 17.2 | 0 | 12.3 | 5.4 |
| Oct | 18° / 11° | 188 | 16.4 | 0 | 11 | 4.9 |
| Nov | 12° / 4° | 166 | 18.2 | 3.4 | 10 | 2.5 |
| Dec | 6° / -1° | 227 | 23 | 15.6 | 9.5 | 0.3 |
Cloud cover in Fall
The sky is clear or mostly clear about 18% of the time across fall.
Chance of precipitation in Fall
Arai gets around 558 mm of rain and snow over 52 wet days across fall. The line is the day-by-day chance of measurable precipitation.
Humidity in Fall
Most of fall feels dry — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Fall
Winds average 7 km/h across fall.
Sunrise & sunset in Fall
Daylight runs from about 12 h 48 min in early September to 9 h 42 min by late November. The lit band spans sunrise to sunset each day.
Solar energy in Fall
Average shortwave solar energy reaching the ground each day across fall, about 3.1 kWh/m².
Hazard calendar for Arai
In fall, Arai overlaps its pacific typhoon season. The full year is below, with each hazard's peak months called out.
Arai sits in the Pacific typhoon belt; the season peaks July–October.
Is fall a good time to visit Arai?
Our two travel scores rate fall for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
fall is a reasonable time to visit Arai for sightseeing.
What to pack for Arai in Fall
From fall's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In fall, Arai sees daytime highs around 18°C and nights near 11°C. Pack a warm layer and rain gear. Worth having: light clothes. About 52 days see rain.
Sea temperature near Arai in Fall
The nearest coast averages about 22°C across fall — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea at the nearest coast (about 16 km away) is warmest in August at about 27°C and coldest in March near 10°C.
It's comfortable for a long swim from Jun 20 to Nov 1 — about 4.4 months when the water holds above 20°C.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 13 | 11 | 10 | 11 | 15 | 20 | 23 | 27 | 25 | 22 | 19 | 15 |
| Comfort | Bracing | Bracing | Bracing | Bracing | Bracing | Cool | Refreshing | Warm | Warm | Refreshing | Cool | Cool |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 13 | Bracing |
| Feb | 11 | Bracing |
| Mar | 10 | Bracing |
| Apr | 11 | Bracing |
| May | 15 | Bracing |
| Jun | 20 | Cool |
| Jul | 23 | Refreshing |
| Aug | 27 | Warm |
| Sep | 25 | Warm |
| Oct | 22 | Refreshing |
| Nov | 19 | Cool |
| Dec | 15 | Cool |
UV index in Arai in Fall
Clear-sky midday UV across fall averages around 6 — enough to warrant sun protection. The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Arai peaks around August 12 at about 10 (very high) — sunscreen, a hat and midday shade are essential. It bottoms out near January 1 at about 2 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — in 9 months of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 2 | 4 | 4 | 7 | 8 | 9 | 9 | 10 | 9 | 5 | 3 | 2 |
| Level | Moderate | Moderate | Moderate | High | Very high | Very high | Very high | Very high | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 2 | Moderate |
| Feb | 4 | Moderate |
| Mar | 4 | Moderate |
| Apr | 7 | High |
| May | 8 | Very high |
| Jun | 9 | Very high |
| Jul | 9 | Very high |
| Aug | 10 | Very high |
| Sep | 9 | Very high |
| Oct | 5 | High |
| Nov | 3 | Moderate |
| Dec | 2 | Moderate |
Air quality in Arai in Fall
Average fine-particle pollution (PM2.5) through the year — so you can see where fall falls, not just the annual average.
Air quality in Arai is worst in April — around 21 µg/m³ PM2.5 (moderate), about 2.2× the cleanest month (December, 10 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 11 | 14 | 20 | 21 | 20 | 18 | 15 | 13 | 12 | 11 | 11 | 10 |
| Level | Good | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Moderate | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 11 | Good |
| Feb | 14 | Moderate |
| Mar | 20 | Moderate |
| Apr | 21 | Moderate |
| May | 20 | Moderate |
| Jun | 18 | Moderate |
| Jul | 15 | Moderate |
| Aug | 13 | Moderate |
| Sep | 12 | Good |
| Oct | 11 | Good |
| Nov | 11 | Good |
| Dec | 10 | Good |
Where is Arai?
Arai sits at 37.0°N, 138.2°E, 175 m above sea level, in Japan. The nearest listed city is Myoko, 4.0 km away.
Topography around Arai
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Arai.
Within 3 km, the terrain around Arai has significant variations in elevation — a maximum elevation change of 416 m around an average of 193 m above sea level; within 16 km, extreme variations in elevation — a maximum elevation change of 2,437 m; within 80 km, extreme variations in elevation — a maximum elevation change of 2,978 m.
The land around Arai is covered by trees (52%) and cropland (30%) within 3 km, trees (79%) within 16 km, and trees (60%) and water (29%) within 80 km.
Japan travel facts
- Travel advisory
- Level 1
- Exercise Normal Precautions
- Power plugs
- Type A / B
- 100 V · 50 / 60 Hz
- Prices
- ≈ 65% of US
- price level, 2025
- GDP per capita
- $35,951
- 2025
- Happiness
- 6.1 / 10
- World Happiness, 2025
- Safe drinking water
- 99%
- of population, 2024
- Homicide rate
- 0.2
- per 100k, 2023
- Road deaths
- 3.6
- per 100k/yr, 2019
- Income group
- High
- World Bank
- English
- Very low
- EF EPI 446
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Arai (37.0006°, 138.2259°, elevation 175 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.